In this video I demonstrate the workings of a Tesla Valve using the combustion of propane as a visible medium. A Tesla valve, called by Tesla a valvular conduit, is a fixed-geometry passive check valve. It allows a fluid to flow preferentially in one direction, without moving parts.
The swirling blue and green flame front in those experiments make burning propane the perfect working fluid to demonstrate how the Tesla valve works.
The video above tells the tale, with high-speed footage showing the turbulence that restricts the reverse flow.
A Tesla valve uses what is now known as the Conda effect – which is the tendency of a flow to follow the nearest wall.The surprise discovery is that in the forward direction, the burning gas actually seems to accelerate as it moves down the valve.